Vesicles are small structures that can be found both inside and outside of cells). They are enclosed by a lipid bilayer and contain liquid or cytoplasm). Vesicles are involved in a variety of cellular processes, including secretion, uptake, and transport of materials within the plasma). They can also be used by cells to organize cellular substances and act as chemical reaction chambers). There are several types of vesicles, including:

• Transport vesicles: These vesicles are involved in transporting proteins within or outside the cell.
• Lysosomes: Lysosomes are vesicles that contain enzymes used to break down waste materials within the cell.
• Secretory vesicles: These vesicles are involved in the secretion of substances such as hormones, neurotransmitters, and enzymes.
• Peroxisomes: Peroxisomes are vesicles that break down toxic compounds within a cell by using oxygen.
• Extracellular vesicles: These are lipid bilayer-delimited particles produced by all domains of life including complex eukaryotes, both Gram-negative and Gram-positive bacteria, mycobacteria, and fungi).

In addition to their cellular functions, vesicles can also appear on the skin as small fluid-filled blisters or sacs. These vesicles can be a symptom of a medical issue or a sign of tissue injury. Some conditions that can cause vesicles on the skin include allergic reactions to drugs, atopic dermatitis, autoimmune disorders, blistering skin diseases, chickenpox, herpes simplex, and bacterial or fungal infections. Treatment for vesicles on the skin depends on the underlying cause and may include over-the-counter remedies or medical attention.